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diff --git a/boost/hana/detail/concepts.hpp b/boost/hana/detail/concepts.hpp
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+/*!
+@file
+Defines concepts from the Standard library.
+
+@copyright Louis Dionne 2013-2016
+Distributed under the Boost Software License, Version 1.0.
+(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+ */
+
+#ifndef BOOST_HANA_DETAIL_CONCEPTS_HPP
+#define BOOST_HANA_DETAIL_CONCEPTS_HPP
+
+#include <boost/hana/config.hpp>
+#include <boost/hana/detail/std_common_type.hpp>
+#include <boost/hana/detail/void_t.hpp>
+
+#include <type_traits>
+
+
+BOOST_HANA_NAMESPACE_BEGIN namespace detail {
+    //////////////////////////////////////////////////////////////////////////
+    // EqualityComparable
+    //////////////////////////////////////////////////////////////////////////
+    template <typename T, typename U = T, typename = void>
+    struct EqualityComparable : std::false_type { };
+
+    template <typename T>
+    struct EqualityComparable<T, T, detail::void_t<
+        decltype(static_cast<T&&>(*(T*)0) == static_cast<T&&>(*(T*)0) ? 0:0),
+        decltype(static_cast<T&&>(*(T*)0) != static_cast<T&&>(*(T*)0) ? 0:0)
+    >> : std::true_type { };
+
+    template <typename T, typename U>
+    struct EqualityComparable<T, U, typename std::enable_if<
+        !std::is_same<T, U>{}, detail::void_t<
+            decltype(static_cast<T&&>(*(T*)0) == static_cast<U&&>(*(U*)0) ? 0:0),
+            decltype(static_cast<U&&>(*(U*)0) == static_cast<T&&>(*(T*)0) ? 0:0),
+            decltype(static_cast<T&&>(*(T*)0) != static_cast<U&&>(*(U*)0) ? 0:0),
+            decltype(static_cast<U&&>(*(U*)0) != static_cast<T&&>(*(T*)0) ? 0:0),
+            typename detail::std_common_type<T, U>::type
+    >>::type> : std::integral_constant<bool,
+        EqualityComparable<T>::value &&
+        EqualityComparable<U>::value &&
+        EqualityComparable<typename detail::std_common_type<T, U>::type>::value
+    > { };
+
+
+    //////////////////////////////////////////////////////////////////////////
+    // LessThanComparable
+    //////////////////////////////////////////////////////////////////////////
+    template <typename T, typename U = T, typename = void>
+    struct LessThanComparable : std::false_type { };
+
+    template <typename T>
+    struct LessThanComparable<T, T, detail::void_t<
+        decltype(static_cast<T&&>(*(T*)0) < static_cast<T&&>(*(T*)0) ? 0:0)
+    >> : std::true_type { };
+
+    template <typename T, typename U>
+    struct LessThanComparable<T, U, std::enable_if_t<
+        !std::is_same<T, U>::value,
+        detail::void_t<
+            decltype(static_cast<T&&>(*(T*)0) < static_cast<U&&>(*(U*)0) ? 0:0),
+            decltype(static_cast<U&&>(*(U*)0) < static_cast<T&&>(*(T*)0) ? 0:0),
+            typename detail::std_common_type<T, U>::type
+        >
+    >>
+        : std::integral_constant<bool,
+            LessThanComparable<T>::value &&
+            LessThanComparable<U>::value &&
+            LessThanComparable<typename detail::std_common_type<T, U>::type>::value
+        >
+    { };
+} BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_DETAIL_CONCEPTS_HPP